JP2759326B2 - Coke production method - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a method for producing coke, and more particularly, to a novel method for producing coke with improved reactivity without sacrificing strength and bulk. It is about the method.

[Prior art] Conventionally, as a method of producing highly reactive coke, there is a method of blending low-carbonity coal from the viewpoint of blending into raw coal, while the furnace temperature is relatively low from the viewpoint of dry distillation conditions. Usually, sub-bituminous coal or lignite is used as the low-carbon coal.

[Problems to be Solved by the Invention] However, according to the conventional method of blending low-rank coal into raw coal as it is, the resulting coke has a high reactivity, but the strength and the bulk are reduced. , From these aspects the reactivity can not always be so high,
There was a problem. Further, in the conventional method of lowering the furnace temperature of the dry distillation, there is a problem that the furnace temperature may be considerably lowered at the time of charging coal blending, and there is a certain limit in terms of furnace body maintenance and management.

An object of the present invention is to provide a novel method for producing a highly reactive causse that can solve the above conventional problems.

[Means for Solving the Problems] The present inventors have conducted intensive studies to achieve such an object, and as a result, using coal having relatively low carbonization as a raw material, the devolatilization treatment was instantaneously performed by rapid pyrolysis. When a large amount of liquid product was obtained, the properties of the char obtained as a pyrolysis residue were examined.As a result, the volatile content was moderately lower than that of the original coal. It was found to be a very light, porous carbonaceous material in the shape of a carbon balloon with a shape different from that of the carbon material. When the char is used as a raw material for coke production, and the char is used as a raw material for coke production, the reactivity and specificity of the coke are not reduced and the reactivity (specifically, for example, a reactivity index of 17) is obtained. The present inventors have found that coke with the above-mentioned improvements can be produced, and have reached the present invention.

That is, the present invention uses a low-carbon coal as a raw material, a char obtained by rapid pyrolysis under conditions of a reaction temperature of 600 to 1000 ° C. and a reaction time of 10 seconds or less, and blends the char into the raw coal when producing coke. SUMMARY OF THE INVENTION The gist of the present invention is a method for producing highly reactive coke, which is used as a carbonaceous material.

Embodiments of the Invention Hereinafter, the method of the present invention will be described in detail with reference to the drawings.
FIG. 1 is a schematic diagram illustrating the production of essential char in the method of producing coke according to the present invention.

As shown in FIG. 1, raw material low-carbon coal pulverized to a predetermined particle size is fed into a vertical tubular flow reactor (3) at a constant feed rate using a coal feeder (1). Do it. On the other hand, the carrier gas heated to a predetermined temperature is also sent to the reactor at the same time, where the raw coal and the high-temperature carrier gas come into contact, and the raw coal is heated in a very short time and thermally decomposed. The solid char in the pyrolysis product is collected as a residue in a char receiver (7), and the gas and tar vapor pass through the next cooling trap (8) and are cooled to form a liquid such as tar. The product is collected in the cooling trap (8), and only gas is discharged out of the system by the blower (10). The method for producing coke according to the present invention is a method in which the char thus obtained is used as a carbon material for blending into ordinary coking coal, and carbonized in an ordinary coke oven to obtain highly reactive coke.

Next, the production conditions of the essential char in the method of the present invention will be described more specifically.

Low-rank coal such as weakly-coking coal or non-coking coal with a low degree of coalification, such as lignite,
Subbituminous coal) can be used. In addition, the coal particle size may be about 3% or less and about 80% or less,
Desirably, coal having a particle size of about 35 mesh or less is used.

Regarding the thermal decomposition of such raw coal, although it depends on the type of coal, the C—C bond is severely cleaved from about 650 ° C., and the yield of hydrocarbon gas and liquid products increases. or,
When the temperature exceeds about 850 ° C., the conversion of the once generated radical component having a high molecular weight to char by virtue of polycondensation becomes severe, and the conversion of carbon into a liquid product starts to decrease again. Therefore, the reaction temperature for rapidly pyrolyzing the raw material coal is 600 to 1000 ° C, preferably about 650 to 850 ° C.

The reaction time of rapid pyrolysis is difficult to determine uniquely because the temperature rise rate changes depending on temperature, residence time, etc.
In about 10 seconds or less, the heating rate of the coal is suitable for rapid heating of several degrees to about 10 ⁶ ° C / second.

Further, as the carrier gas of the raw material coal, nitrogen, argon, an inert gas such as combustion exhaust gas, or
An active gas such as hydrogen, methane, or coke oven gas is used, and the temperature of the carrier gas is suitably about 600 to 1000 ° C.

EXAMPLES Next, the present invention will be described more specifically with reference to examples.
In the examples, "%" is "% by weight" unless otherwise specified.

In addition, among properties of cokes, particularly important rotational strength and reactivity were tested as follows in accordance with JIS K2151.

(1) Rotational strength (according to a drum test): The drum has a thickness of 9 mm, an inner diameter of 150 mm, and a length of 150 mm, and six blades of 9 mm in thickness and 250 mm in width are vertically fixed on the inner surface.
Put 10kg of lump coke of 50mm or more into this drum and 15rpm
And then sieve through 50 mm, 25 mm, and 15 mm sieves respectively, and express the strength with respect to the number of rotations as a percentage of the weight on the sieve relative to the sample. In this case, it is displayed as ▲ DI ¹⁵⁰ ₁₅ ▼.

(2) Reactivity: Fill 840 to 1680 μm coke flour as a sample into a reaction tube maintained at 950 ° C. to a specified height. Here, carbon dioxide gas is passed at a flow rate of 50 cc / min, and unreacted carbon dioxide gas is absorbed and removed with a caustic potash solution, the flow rate of the generated carbon monoxide is determined, and the flow rate m1 per minute is defined as the reactivity index.

[Examples 1 and 2] Nitrogen gas at a flow rate of 10 / min was used as a carrier gas from a low-carbon coal weakly caking coal (produced in Australia, volatile matter: 36%) at a reaction temperature of about 850 ° C. A rapid pyrolysis was performed with a reaction time of 0.3 seconds to obtain a residue char. Its properties are as shown in Table 1 below.

Next, the above char obtained by the rapid pyrolysis of low-carbon coal is used as a raw material from the Gouniera coal (strongly caking coal produced in Australia) having the properties shown in Table 1 below. A mixture mixed with the Gunniera coal at the ratios shown in Table 3 below was charged into a test furnace (charge amount 15 g), and coke was produced under canning conditions shown in Table 2 below. The properties of the obtained coke are shown in Table 3 below.

[Comparative Examples 1 to 3] Each of the Gunniera charcoal alone (Comparative Example 1) and a mixture of Gunniera charcoal breathing coke breathes (see Table 1 below for the properties) (Comparative Examples 2 and 3) were used. , And coke was manufactured under the baking conditions shown in Table 2 below. The properties of the obtained coke are summarized and shown in Table 3 below.

From Table 3 above, it can be seen that the coke of the example obtained by the method of the present invention has the same rotational strength as that of the conventional coke obtained in the comparative example, and has much higher reactivity. I understand.

[Effects of the Invention] As described in detail above, according to the method of the present invention, the charcoal obtained by rapid pyrolysis using low-carbon coal as a raw material is blended into the raw coal for coke production, whereby strength and bulkiness are improved. Excellent reactivity (reactivity index
(17 or more) can be easily produced, and its industrial utility value is extremely large.

[Brief description of the drawings]

FIG. 1 is a schematic diagram illustrating the production of a char used in the method of the present invention. 1 ... Coal feeder, 2 ... Carrier gas preheating furnace,
3 ... Reactor, 4 ... Reactor, 5 ... Carrier gas flow meter, 6 ... Differential pressure gauge, 7 ... Char receiver, 8 ... Liquid product collector (cooling trap), 9 ... Gas sampler,
10 …… Blower, 11… Gas meter

──────────────────────────────────────────────────続 き Continuation of front page (56) References JP-A-52-112602 (JP, A) JP-A-54-141802 (JP, A) JP-A-54-112901 (JP, A) JP-A-56-112 136882 (JP, A) (58) Field surveyed (Int. Cl. ⁶ , DB name) C10B 57/04

Claims (1)

(57) [Claims] 1. A low carbonized coal is used as a raw material and has a reaction temperature of 600 to 100.
A method for producing highly reactive coke, comprising using a char obtained by rapid pyrolysis under the conditions of 0 ° C. and a reaction time of 10 seconds or less as a carbon material for blending into raw coal when producing coke. .